The legal left is at a crossroads. With Supreme Court Justice Brett Kavanaugh’s confirmation, and with President Donald Trump filling appellate judgeships at a breakneck pace, the federal courts are likely to lean right for the foreseeable future. Landmark decisions such as Roe v.Wade are in peril. Laws enacted by progressive state legislatures, or by a future Democratic Congress and president, are at heightened risk of being struck down by a coterie of federal judges that is not just conservative but also partisan and activist.

We have been here before. In the early part of the 20th century, a conservative Supreme Court gutted state and federal laws limiting child labor, setting minimum wages, regulating banks, and pursuing other progressive agenda items that had wide popular support. Progressive politicians and intellectuals responded by attacking the court’s institutional legitimacy and calling the very idea of judicial supremacy into question. As President Franklin Roosevelt said in one of his “fireside chats” in 1937, “We have … reached the point as a nation where we must take action to save the Constitution from the court.” Roosevelt responded with a court-packing plan that—though unsuccessful on its own terms—did what it was intended to do. An overawed Supreme Court allowed Roosevelt’s Second New Deal to proceed.

At the dawn of the 21st century, we found ourselves at a similar juncture. The court’s 5–4 decision in Bush v. Gore laid bare the reality that rulings handed down by judges are—at least at times—politics by other means. That decision inspired many progressives to ask whether a transparently partisan court should continue to enjoy the power to override the electorate’s will. This time, however, the modal response from the left was not an all-out attack on the normative foundations of judicial supremacy. Progressives focused instead on ways to vindicate their values while preserving the enormous power of federal courts.

At the dawn of the 21st century, we found ourselves at a similarjuncture.

Fast-forward to 2018. A Republican again occupies the White House without having won the popular vote, and another right-wing takeover of the courts is well underway. And yet again, the left seems almost certain to divide over how to deal with a right-wing judiciary. Some will say that progressives’ continued embrace of judicial supremacy post–Bush v. Gore turned out to be a mistake. By conceding the institutional legitimacy of an activist and partisan Supreme Court, progressives paved the way for decisions striking down common-sense gun regulations, corporate campaign finance laws, key components of Obamacare, voting rights protections, and much more.

In the eyes of those who subscribe to this view, progressives gave up on democracy. And they effectively tied their own hands by acknowledging that the law is whatever the Supreme Court says it is, which all too often means that the law is whatever the Republican Party and the Federalist Society want it to be.

Others will respond that the decision by progressives after Bush v. Gore to stay faithful to judicial supremacy brought some significant gains. They will point toward post-2000 Supreme Court decisions that affirmed important progressive values while striking down popularly enacted laws, including decisions that barred the execution of intellectually disabled individuals, that outlawed the horrific practice of mandating life without parole sentences for minors, that recognized the due process rights of Guantánamo detainees, and that legalized same-sex marriage for all 50 states. The wiser approach, they will argue, is the one that progressives most recently followed: choosing to fight inside the court rather than against the court.

The two of us find ourselves on opposite sides of this divide. In a series of posts, we will try to convince each other that our own view is the right one for the left. If history is any guide, the left needs to have this debate. Now.